Patients with glaucomatous disease frequently appear in clinical examinations because they are common, have chronic slowly progressive pathology, and often pose a multi-disciplinary diagnostic or management dilemma. Although most of the examination will be focused on the optic disc, candidates should remember to look at the anterior segment for clues to secondary glaucomas.
When examining a patient with glaucoma, the aims of the examination are to determine:
Detection of one sign (e.g. a closed angle) should prompt the candidate to look for associated signs (e.g. a peripheral iridectomy). Always be aware that patients with “glaucoma” may instead have neuro-ophthalmic problems and have been mis-diagnosed previously. The excellent candidate will always begin their assessment by asking themselves: “does this patient actually have glaucoma?”
Begin with general inspection.
Estimate depth with the Van Herick technique:
Look carefully for an anterior chamber tube.
Fuch’s heterochromic iridocyclitis
Pigment dispersion syndrome
Due to the semi-invasive nature of this procedure, it is rare that it will be allowed in examinations. Nevertheless the candidate should know how to perform gonioscopy and ask for the findings. The procedure is outlined below:
a) Open or Closed?
Irido-trabecular (ITC) contact can be:
There are several grading scales for documenting how open the angle is. The most direct method is to document what structures (described above) are visible. Other grading systems include:
Increases in angle from Grade 0 (0°) to Grade 4 (35-45°).
Increases in angle from Grade A to E
Decreases in angle from Grade I to IV
Gonioscopy should be performed at rest (with minimal pressure on the cornea) to show the apparent insertion of the iris, and dynamically (by indenting the cornea with the gonioscopy lens) to assess the true iris insertion point. This is only possible with non-flanged gonioscopy lenses. The findings should be recorded together: e.g. “TM → CB (indent)”.
c) Trabecular Meshwork Hyperpigmentation
d) Iris Insertion
Concave (bowed posteriorly), plateau, flat, convex (bowed anteriorly).
Remember that each mirror in an indirect gonioscope look at the opposite angle (the superior mirror looks at the inferior angle etc.). Always compare both eyes - 360° angle recession can be mistaken for just a “deep angle” if only one eye is inspected.
Of all the components of the glaucoma examination, inspection of the optic disc is often the most useful. Always inspect both optic discs and compare them.
β-zone PPA in particular is associated with glaucoma progression.
Use red free (green light).
Look closely for loss of striations, especially if a notch has been observed.
All rights reserved. No part of this publication which includes all images and diagrams may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the authors, except in the case of brief quotations embodied in critical reviews and certain other noncommercial uses permitted by copyright law.
Vitreoretinal Surgery Online
This open-source textbook provides step-by-step instructions for the full spectrum of vitreoretinal surgical procedures. An international collaboration from over 90 authors worldwide, this text is rich in high quality videos and illustrations.